B1235 Diagnostic Trouble Code

B1235 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a B1235 diagnostic trouble code may include:

Lack of power
Faulty O2 Sensor
Poor acceleration
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly

Possible Causes :

Defective ECU strategies or components will prevent proper regeneration
The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0307 for number 7.

Repair Processes :

With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for.

Process Tips

Diagnostic trouble code B1235 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before B1235.

Fortunately, B1235 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B1235 Trouble Code For Specific Cars

B1235 Hudson Commodore Ride Control RR Shock Actuator Circuit Short To Ground
B1235 Pontiac 6000 Exhaust Pressure Control Valve High
B1235 Fiat Scudo Ii Lateral Accelerometer Sensor Circuit Open
B1235 Bsa Fwd Cruise Control/Brake Switch A Circuit Malfunction
B1235 Sunbeam-talbot Tiger Memory #1 output Short to Ground
B1235 Daihatsu Sonica Glow Plug Circuit Low Input (Bank #2)
B1235 Renault Master 2 Headlamp Aim Output Relay Circuit Short To Battery